Environmental contamination control device

ABSTRACT

An improved device for a medical treatment station which may include inducing and collecting sputum without contaminating the environment. A patient is positioned to inhale an aerosol from a discharge hose connected to a nebulizer. Sputum, excess aerosol and room air are drawn through an ultra-high-efficiency filter system to remove preferably at least 99.97 percent of 0.3 micron and larger particles from the air. The purified air is returned to the room, except for a controlled portion which is diverted to the nebulizer for delivering a controlled density aerosol. The filter system preferably includes a gross particle filter and a pre-filter in addition to the ultra-high-efficiency filter. The aerosol discharge hose is positioned in a cowl which directs room air, exhaled air, sputum and excess aerosol to the filter. The highly contaminated aerosol discharge hose, cowl, gross particle filter and pre-filter, and in severe contamination cases the housing and the ultra-high-efficiency filter, are all disposable.

United States Patent 1 Gauthier et al.

1 1 ENVIRONMENTAL CONTAMINATION CONTROL DEVlCE [75] Inventors: WilliamD. Gauthier, Sylvania Township; J eter L. Ridley, Toledo, both of Ohio[7 3 Assig neez iv Champion Spark Plug Company, Toledo, Ohio [22] Filed:Feb. 22, 1971 211 Appl. No.: 117,391

[52] US. Cl. 128/2 R, 98/115 LH, 128/2 F,

128/194 [51] Int. Cl A61b l0/00 [58] Field of Search 128/1, 2 R, 2 C,

128/2F, 139, 132, 172, 191 R, 191 A, 194; 98/115 LH, 36

[56] References Cited UNITED STATES PATENTS 3,665,917 5/1972 Jensen128/2 R 3,121,618 2/1964 Yerzley 98/115 LH 3,492,987 2/1970 Parker 128/13,511,162 5/1970 Truhan 128/191 X 2,840,417 6/1958 Dorsak et al. 128/186X 2,209,054 ,7/1940 Doud et al. 128/172 X 2,182,973 12/1939 Taylor.128/191 R 2,111,874 3/1938 Steiner 128/191 A 3,107,974 1 10/1963Potapenko 128/] R X 3,301,167 1/1967 Howard et al. 98/115 2,737,6953/1956 Sokolik 128/139 X 3,565,072 2/1971 Gauthier 128/191 A OTHERPUBLICATIONS Proceedings of Staff Meetings of the Mayo Clinic;

[ 1 July 17, 1973 Mayo Association, Vol. 38, No. 3, Jan. 30, 1963, pp.51-59.

American Review of Respiratory Diseases, 1967, pp. 1246-1249.

Primary Examiner-Kyle L. Howell Attorney0wen & Owen [57] ABSTRACT Animproved device for a medical treatment station which may includeinducing and collecting sputum without contaminating the environment. Apatient is positioned to inhale an aerosol from a discharge hoseconnected to a nebulizer. Sputum, excess aerosol and room air are drawnthrough an ultra-high-efficiency filter system to remove preferably atleast 99.97 percent of 0.3 micron and larger particles from the air. Thepurified air is returned to the room, except for a controlled portionwhich is diverted to the nebulizer for delivering a controlled densityaerosol. The filter system preferably includes a gross particle filterand a prefilter in addition to the ultra-high-efficiency filter. Theaerosol discharge hose is positioned! in a cowl which directs room air,exhaled air, sputum and excess aerosol to the filter. The highlycontaminated aerosol discharge hose, cowl, gross particle filter andpre-filter, and in severe contamination cases the housing and theultrahigh-efficiency filter, are all disposable.

13 Claims, 5 Drawing Figures ENVIRONMENTAL CONTAMINATION CONTROL DEVICEBACKGROUND OF THE INVENTION This invention relates to a device for usein medical diagnosis and treatment and, more particularly, to animproved device for administering medical aerosols to a patient withoutcontaminating the environment.

It is sometimes desirable for a physician to cause a patient toexpectorate sputum. However, precautions must be taken not tocontaminate the environment, since the patient may have a communicabledisease. In some cases, a sample of the sputum must be collected. Sputumsamples may, for example, be required for bacteriologic, cytologic andmycologic diagnosis. Sputum induction may also follow treatment progressin tuber culosis and other infectious pulmonary diseases. When a patientis induced to expectorate sputum and for some treatments, it is alsodesirable to administer an aerosol withoutcontaminating the environment.Aerosols may be used, for example, for tracheo bronchial particledeposition and cleansing or for administering anesthesia.

There is a growing professional concern regarding the spread ofinfections in limited but potentially dangerous environments.Cross-contamination, be it physically disseminated by a device orhumanly dispersed, is often a topicof discussion in professionaljournals and circles. With certain strains of organisms becomingresistant to treatment through a bio-physical process of mutation,breaking the cross-infection-re-infection cycle in certain critical butvulnerable environments is becoming increasingly difficult. Evolutionofthis infection phenomenon is as broad as ones recognition of man and hisinstruments ability to harbor and transmit the organisms unconsciouslythrough daily routine.

There has also been increased concern for protecting personnel workingin critical environments from infection and from inhaling aerosoldisseminated particles. If, for example, an aerosol is used duringtreatment of a tuberculosis patient, there is a hazard that attendingpersonnel will breathe excess aerosol or will become infected fromsputum expectorated by the patient. Further problems may be caused bythe depositionof sputum and aerosol particles on walls,ceilings, floorsand furnishings in hospital, home and clinic environments. It istherefore desirable to have a portable device for administering anaerosol to a patient without contamihating the environment with sputumand excess aerosol.

SUMMARY OF THE INVENTION According to the present invention, an improveddevice is provided for administering therapeutic or cough inducingaerosols and for collecting sputum samples without contaminating theenvironment with excess aerosol medicament or expectorated sputum. Asused herein, sputum is intended to include not only expectorated matter,mucus, or the like, but exhaled contaminated aerosols and particulatematter. The device generally comprises an enclosed housing having an airinlet and an air outlet. An ultra-high-efficiency filter capable ofremoving 99.95 percent of 1 micron and larger particles from air andpreferably capable of removing at least 99.97 percent of 0.3 micron andlarger particles from air is placed between the air inlet and the airoutlet in the housing. A blower is mounted between the tilter and theair outlet to cause air to flow through the air inlet, the filter andthe air outlet. A cow] is releasably attached to the housing to directair, sputum and aerosol particles to the air inlet.

In a preferred embodiment, the filter comprises a disposable grossparticle filter, a disposable pre-filter and a disposableultra-high-efficiency filter. Contaminated air is sequentially filteredby the gross particle filter, the pre-filter and theuItrahigh-efficiency filter. The gross particle filter is designed forreplacement after each use of the environmental contamination controldevice, while the pre-filter is replaced periodically at relativelyshort intervals, e.g., every 30 days, and the ultra-highefficiencyfilter is replaced periodically at longer intervals, e.g., every year.When required, sputum samples are expectorated into a disposablecontainer positioned adjacent the filter inlet.

The housing of the environmental contamination control device isadjustably mounted on a portable carriage. The position of the housing:is adjustable for use with a patient while lying or sitting on a bed,or while sitting in a chair. A conventional nebulizer, preferably anultrasonic nebulizer, is also mounted on the carriage. A portion of thefiltered air leaving the air outlet is diverted through an adjustablecontrol valve to the nebulizer and an aerosol supply hose is attachedfrom the nebulizer to a clamp on the housing. An aerosol dis charge hoseis removably attached to the supply hose and extends to within theconfines of the cowl. The control valve is used to adjust the density ofthe aerosol delivered to the cowl.

During normal use, the cowl, the aerosol discharge hose and the grossparticle filter are contaminated by aerosol, exhaled air and sputum.Each of these parts is constructed from inexpensive materials and eachis designed to be readily replaceable and disposable by incineration.The pre-filter and the uItra-high-efficiency filter are usually notreplaced after each use. However, where highly toxic aerosols or highlyinfectious organisms are involved, the pre-filter, theultra-highefficiency filter and the housing are also disposable. In suchcases, the blower, the carriage and the nebulizer are the only partssaved. These parts may be cleaned by gas sterilization, but arenotcontaminated in normal use. l

Accordingly, it is a primary object of the invention to provide animproved device for controlling environmental contamination fromaerosols being administered to a patient or from similar medicalprocedures.

Another object of the invention is to provide an improved device forinducing sputum and reducing environmental contamination from theinduced sputum.

Another object of the invention is to provide an improved device forreducing environmental contamination during inhalation therapy in whichall contaminated parts of the device are disposable.

Still another object of the invention is to provide an improved airfiltering device for reducing environmental contamination while applyingan aerosol to a patient and in which filtered exhaust air from thedevice is used in delivering the aerosol.

Other objects and advantages of the invention will become apparent fromthe following detailed description, reference being made to theaccompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in perspective of animproved device according to the present invention for delivering anaerosol to a patient and for preventing environmental contamination fromsputum, exhaled air and excess aerosol;

FIG. 2 is a side elevational view in section of an improvedenvironmental contamination control device according to the presentinvention;

FIG. 3 is a front end elevational view of an improved environmentalcontamination control device according to the present invention;

FIG. 4 is a rear end elevational view of an improved environmentalcontamination control device according to the present invention; and

FIG. 5 is a fragmentary cross-sectional view of a control valve fordiverting a portion of the filtered exhaust air to a nebulizer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, animproved device is shown according to the present invention foradministering medical aerosols to a patient 11 without contaminating theenvironment. The device 10 generally comprises a filter and blowerhousing 12, a cowl 13 and a nebulizer 14 mounted on a carriage 15.During operation, highly filtered, and thus clean, exhaust air from thehousing 12 is supplied through a hose 16 to the nebulizer 14. Thenebulizer l4 delivers an aerosol through a supply hose 17 and adischarge hose 18 to within the confines of the cow] 13.

The patient 11 is positioned with his face adjacent a flared or enlargedopening 19 defined by the cowl 13. The patient 11 inhales a concentratedaerosol discharged from the hose 18, which may induce a coughing spasm.When the patient 11 is induced to cough, he exhales violently and maydischarge sputum into the cowl 13. Room air, exhaled air, sputum andexcess aerosol are drawn into the housing 12 wherein the air is highlyfiltered and cleaned. The filtered air is discharged at a rear end 20 ofthe housing 12, with a portion of the air being diverted into the hose16.

The carriage includes a base 23 which is mounted on wheels 24 formobility. A pair of parallel, vertical support members 25 are attachedto the base 23. The housing 12 is positioned between and adjustablyattached to the support members 25 by means of trunnions 26. Thetrunnions 26 permit a vertical and an angular adjustment of the positionof the housing 12 to facilitate using the device 10 with patients invarious positions, for example, lying or sitting on a bed or sitting ona chair. The nebulizer 14 is also attached to one of the support members25.

The nebulizer 14 may be any suitable commercially available unit. Onetype of nebulizer found to be particularly suitable is that shown in USPat. No. 3,387,607 entitled Apparatus for Inhalation Therapy. In somecases where an aerosol is not required for causing a coughing spasm toinduce sputum, the nebulizer 14 may be omitted.

Referring now to FIGS. 2-4, the environmental contamination controldevice 10 is shown in greater detail. The housing 12 generally comprisesa box constructed from a relatively inexpensive disposable material,such as plywood. An air inlet 27 is formed in one end of the housing 12while a rigid plate 28 closes the other end of the housing 12. Anopening 29 in the plate 28 defines an air outlet. A conventional blower30, such as a squirrel cage blower, is mounted on the plate 28 to drawair through the cowl l3 and the housing 12 and exhaust such air throughthe outlet 29. A switch 31 is mounted on the plate 28 for controllingthe blower 30. A bracket 32 is also mounted on the back plate 28 forstoring a power cord 33 for the device 10 when it is not in use. Theback plate 28 is removably attached to the housing 12 by means of screws34 such that the back plate 28 and the blower 30 may be removed as aunit for maintenance, gas sterilization or attachment to a new housing12. All permanent parts of the device 10 are mounted either on thecarriage 15 or on the back plate 28.

A wire cowl frame 37 is provided with an end 38 which snaps or tightlyfits into the air inlet 27 of the housing 12. The cowl 13 preferablycomprises a thin sheet of a transparent synthetic resinous material. Thecowl 13 is attached to the housing 12 by folding over the end 38 of theframe 37 and inserting the end 38 into the air inlet 27, where it isheld in place by friction and compression. An extended end 39 of thecow] 13 is folded over an enlarged wire loop 40 which forms a projectingend of the frame 37 and defines the opening 19. The frame 37 ispreferably constructed from rigid wire and is coated with a synthetlcresin which prevents corrosion and is easily cleaned and disinfected.The aerosol discharge hose 18 is releasably held in place by a connector41 which is attached to the housing 12 and the hose 17. The hose 18extends through a sized opening 42 in the cowl 13. The aerosol dischargehose 18 is also constructed from an inexpensive disposable material,such as a synthetic resin, formed into a desired shape to direct thedischarged aerosol. A disposable clip may also be used to give the hose18 a desired shape and to retain it in position. The hose 18 isremovable from the connector 41 and disposable with the cowl 13 aftereach use of the device 10.

A filter system 43 is positioned within the housing 12 to removeparticles from air flowing through the housing 12. The heart of thefilter system 43 is an ultra-highefficiency filter element 44 whichremoves substantially all particles from air passing through the housing12. In its preferred form, the filter element 44 removes at least 99.95percent of 1 micron and larger particles from air, while in its mostpreferred form, the filter element 44 will remove at least 99.97 percentof 0.3 micron and larger particles. Filters of this type arecommercially available and are typically constructed fromcellulose-asbestos-fiber paper, glass and glass-asbestos fiber papers,ceramic fiber paper, compressed glass fibers, or composite beds of glasswool pads. Since ultrahigh-efficiency filters of this type have a higherresistance to air flow than less efficient filters, the filter isusually pleated to provide an increased filter surface area in a smallfrontal area. The ultra-high-efficiency filter 44 is disposable and mustbe replaced when it becomes loaded with particles from the air. Toreduce loading of the filter 43, a gross particle filter 45 and apre-filter 46 are placed upstream of the ultra-highefficiency filter 44.The gross particle filter 45 may, for example, comprise a relativelythin mat of rayon fiber, while the pre-filter 46 may comprise a thickerglass fiber screen. The gross particle filter 45 is designed forreplacement after each use of the device 10, while the pre-filter 46 isonly periodically replaced, for example, every 30 days.

Referring now to FIGS. 2, 4 and 5, a control valve 47 is shown fordiverting a selected or controllable portion of the clean air exhaustedfrom the blower 30 to the air hose 16 which connects to the nebulizer14. The control valve 47 includes an inlet member 48 which is positionedto open into the airstream from the blower 30. Air passes through theinlet 48 and through the valve 47 directly into the hose 16. The valve47 also includes a closure member 49 which is rotated by means of a knob50. The closure member 49 rotates between an open position shown insolid in FIG. 5 and a closed position shown in dashed lines in FIG. 5.The closure member 49 may be positioned with the knob 50 to give acontrolled air flow in the hose 16 to deliver a predetermined aerosolconcentration to the cowl 13. When the aerosol is not required and thenebulizer 14 is omitted, the valve 47 may of course be omitted.

It will be appreciated that although a single preferred embodiment ofthe improved environmental contamination control device has beendescribed, various modifications and changes may be made withoutdeparting from the spirit and the scope of the invention hereinafterclaimed.

What we claim is:

1. An improved device for reducing environmental contamination duringmedical treatment or diagnosis of a problem of a patient comprising, incombination, an enclosed housing having an air inlet and an air outlet,a cowl constructed from a thin film such that it is disposable after asingle use of said device, wire-like frame means releasably attachingsaid cow] to said housing, means releasably mounting said wire-likeframe means on said housing adjacent said air inlet, said cowl beingpositioned on said frame means to extend completely around said airinlet to direct an aerosol and sputum from the patient to said airinlet, filter means positioned in said housing between said air inletand said air outlet, said filter means removing substantially allparticles larger than one micron from air passed through said housing,blower means positioned in said housing between said filter means andsaid air outlet for causing air to flow sequentially through said cowl,said air inlet, said filter means and said air outlet, and means on saiddevice for supplying an aerosol to within the confines of said cow] tobe breathed by the patient. i

2. An improved device for reducing environmental contamination, asdefined in claim 1, wherein said means for supplying an aerosol includesan aerosol supply hose located exterior to said cowl, an aerosol hosesection disposable after a single use having an outlet positioned withinthe confines of said cowl and an inlet exterior to said cowl, andcoupler means releasably connecting said disposable aerosol hose sectioninlet to said aerosol supply hose.

3. An improved device for reducing environmental contamination, asdefined in claim 2, and including means for adjusting said disposableaerosol hose to direct the aerosol in a predetermined direction withinthe confines of said cowl.

4. An improved device for reducing environmental contamination during aninduced sputum, as defined in claim 1, wherein said filter meansincludes an ultrahigh-efficiency filter means for removing at least99.97

percent of 0.3 micron and larger particles from air passed through saidhousing.

5. An improved device for reducing environmental contamination during aninduced sputum, as defined in claim 4, wherein said filter means furtherincludes a gross particle filter disposable after a single use, andmeans removably mounting said gross particle filter between said airinlet and said ultra-high-efficiency filter, whereby said gross particlefilter reduces loading of said ultra-high-efficiency filter.

6. An improved device for reducing environmental contamination during aninduced sputum, as defined in claim 1, wherein said means for supplyingan aerosol includes an ultrasonic nebulizer, and means for supplying acontrolled flow of air to said ultrasonic nebulizer.

7. An improved device for reducing environmental contamination during aninduced sputum, as defined in claim 6, wherein said means for supplyinga controlled flow of air to said ultrasonic nebulizer includes anadjustable valve, an air hose connecting said valve to said nebulizer,and means mounting said adjustable valve to divert a controlled portionof the filtered air leaving said blower means into said hose.

8. An improved device for reducing environmental contamination, asdefined in claim 7, wherein said means for supplying an aerosol furtherincludes an aerosol supply hose positioned exterior to said cowl, meansconnecting said supply hose to said nebulizer, an aerosol hose sectiondisposable after a single use having an outlet positioned within theconfines of said cowl and an inlet exterior to said cow], and couplermeans releasably connecting said disposable hose section inlet to saidaerosol supply hose.

9. An improved device for reducing environmental contamination, asdefined in claim 1, and further including a mobile carriage, meansattaching said housing to said carriage, and means for adjusting theposition of said housing on said carriage to direct said cowl to receivesputum from a patient.

10. An improved device for reducing environmental contamination, asdefined in claim 1, wherein said housing is disposable after saidhousing becomes con .taminated.

11. An improved device for reducing environmental contamination, asdefined in claim 1, wherein said disposable cowl comprises a thin filmof synthetic resinous material.

12. An improved device for reducing environmental contamination duringmedical treatment or diagnosis of a problem of a patient comprising, incombination, an enclosed housing having an air inlet and an air outlet,filter means positioned in said housing between said air inlet and saidair outlet for removing at least 99.97 percent of 0.3 micron and largerparticles from air passed through said housing, blower means positionedin said housing between said filter means and said air outlet forcausing air to flow through said air inlet, said filter means and saidair outlet, aerosol generating means, means mounting said aerosolgenerating means on said device for supplying an aerosol to adjacentsaid air inlet, cowl means attached to said housing for directing air,sputum from the patient and the aerosol to said air inlet, and means forsupplying a flow of filtered air from said air outlet to said aerosolgenerating means, said air supplying means including an adjustablevalve, an air hose connecting said valve to said aerosol generatingmeans, and means connecting said adjustable valve to said housing todivert a controlled portion of the filtered air from said blower meansto said hose.

13. An improved device for reducing environmental contamination, asdefined in claim 12, wherein said aerosol generating means includes anultrasonic nebulizer.

1. An improved device for reducing environmental contamination during medical treatment or diagnosis of a problem of a patient comprising, in combination, an enclosed housing having an air inlet and an air outlet, a cowl constructed from a thin film such that it is disposable after a single use of said device, wirelike frame means releasably attaching said cowl to said housing, means releasably mounting said wire-like frame means on said housing adjacent said air inlet, said cowl being positioned on said frame means to extend completely around said air inlet to direct an aerosol and sputum from the patient to said air inlet, filter means positioned in said housing between said air inlet and said air outlet, said filter means removing substantially all particles larger than one micron from air passed through said housing, blower means positioned in said housing between said filter means and said air outlet for causing air to flow sequentially through said cowl, said air inlet, said filter means and said air outlet, and means on said device for supplying an aerosol to within the confines of said cowl to be breathed by the patient.
 2. An improved device for reducing environmental contamination, as defined in claim 1, wherein said means for supplying an aerosol includes an aerosol supply hose located exterior to said cowl, an aerosol hose section disposable after a single use having an outlet positioned within the confines of said cowl and an inlet exterior to said cowl, and coupler means releasably connecting said disposable aerosol hose section inlet to said aerosol supply hose.
 3. An improved device for reducing environmental contamination, as defined in claim 2, and including means for adjusting said disposable aerosol hose to direct the aerosol in a predetermined direction within the confines of said cowl.
 4. An improved device for reducing environmental contamination during an induced sputum, as defined in claim 1, wherein said filter means includes an ultra-high-efficiency filter means for removing at least 99.97 percent of 0.3 micron and larger particles from air passed through said housing.
 5. An improved device for reducing environmental contamination during an induced sputum, as defined in claim 4, wherein said filter means further includes a gross particle filter disposable after a single use, and means removably mounting said gross particle filter between said air inlet and said ultra-high-efficiency filter, whereby said gross particle filter reduces loading of said ultra-high-efficiency filter.
 6. An improved device for reducing environmental contamination during an induced sputum, as defined in claim 1, wherein said means for supplying an aerosol includes an ultrasonic nebulizer, and means for supplying a controlled flow of air to said ultrasonic nebulizer.
 7. An improved device for reducing environmental contamination during an induced sputum, as defined in claim 6, wherein said means for supplying a controlled flow of air to saId ultrasonic nebulizer includes an adjustable valve, an air hose connecting said valve to said nebulizer, and means mounting said adjustable valve to divert a controlled portion of the filtered air leaving said blower means into said hose.
 8. An improved device for reducing environmental contamination, as defined in claim 7, wherein said means for supplying an aerosol further includes an aerosol supply hose positioned exterior to said cowl, means connecting said supply hose to said nebulizer, an aerosol hose section disposable after a single use having an outlet positioned within the confines of said cowl and an inlet exterior to said cowl, and coupler means releasably connecting said disposable hose section inlet to said aerosol supply hose.
 9. An improved device for reducing environmental contamination, as defined in claim 1, and further including a mobile carriage, means attaching said housing to said carriage, and means for adjusting the position of said housing on said carriage to direct said cowl to receive sputum from a patient.
 10. An improved device for reducing environmental contamination, as defined in claim 1, wherein said housing is disposable after said housing becomes contaminated.
 11. An improved device for reducing environmental contamination, as defined in claim 1, wherein said disposable cowl comprises a thin film of synthetic resinous material.
 12. An improved device for reducing environmental contamination during medical treatment or diagnosis of a problem of a patient comprising, in combination, an enclosed housing having an air inlet and an air outlet, filter means positioned in said housing between said air inlet and said air outlet for removing at least 99.97 percent of 0.3 micron and larger particles from air passed through said housing, blower means positioned in said housing between said filter means and said air outlet for causing air to flow through said air inlet, said filter means and said air outlet, aerosol generating means, means mounting said aerosol generating means on said device for supplying an aerosol to adjacent said air inlet, cowl means attached to said housing for directing air, sputum from the patient and the aerosol to said air inlet, and means for supplying a flow of filtered air from said air outlet to said aerosol generating means, said air supplying means including an adjustable valve, an air hose connecting said valve to said aerosol generating means, and means connecting said adjustable valve to said housing to divert a controlled portion of the filtered air from said blower means to said hose.
 13. An improved device for reducing environmental contamination, as defined in claim 12, wherein said aerosol generating means includes an ultrasonic nebulizer. 